Groucho, Harpo and Chico are still the funniest members of the Marx family, but Karl Marx gets plenty of laughs in Detroit Rep's staging of “Capital.” The inspired new comedy from James Armstrong recasts the philosopher and economist not as the wild-bearded father of communism but as the real-life father of a demanding teen who gets caught up in a zany farce.

Rep vet Harry Wetzel does double duty in this production. He is responsible for the set design, which includes a writing desk stage right that is seemingly held together by pages of Karl’s manuscripts. He also plays the lead role, a man who happiest when he is scratching out new pages of what will eventually be "Das Kapital," his epic three-volume tome.

The play is set in 1858, when Marx was a London correspondent for the New York Herald Tribune. He has a new column ready to mail, but he gets distracted by teenage daughter Jenny (Lulu Dahl), who insists that she must have a new silk bonnet to replace her old straw one. Not surprisingly, her father is not about to squander their money on such a symbol of conspicuous consumption.

To settle their difference of opinion, Jenny insists on calling in a random man (Ben Will, playing multiple roles) from the street. Before they can solicit his opinion, the stranger tries to sell them his new brand of sealing wax. He even has a contagious little jingle to go with the pitch.

By coincidence (one of several in the show), the man also has a letter written by Charles Dickens (yes, that Charles Dickens) in which the author reveals his plans to leave his wife and run off with actress Nelly Ternan (Sara Catheryn Wolf). Marx takes it upon himself to return the letter to its rightful owner, but runs into complications when Nelly arrives on the scene and insists that the letter be given to her.

Marx must now put his philosophy into practice and decide what to do. A letter’s purpose is to be delivered and read, so why not give it to his newspaper back in New York? Then again, shouldn’t a citizen (even one as well-known as Dickens) be able to keep details of his private life away from prying eyes?

By the end of the first act, characters tackle one another for control of the letter as it is snatched from hand to hand in the city park that Wetzel has fashioned stage left.( No one gets credit for the fight choreographer, though he or she probably should.) The battle over the letter continues well after intermission.

Playwright Armstrong has created a work that is at once old-fashioned and modern, cerebral and slapstick. Jenny might as well be talking about the latest iPhone rather than a new hat. The debate over what to print and the sanctity of the private versus the public continues to rage today courtesy of our tabloid culture.

“Capital” director Leah Smith remains in complete command of this tricky material and encourages her cast to head way over the top. This isn’t hard for Wolf, whose flighty stage star Nelly regularly bursts into soliloquy when she thinks she hears a cue. The skirt of her ankle-length hoop dress has a mind of its own, entering a scene long before she does.

With all of this kookiness spinning around him, you might assume that Marx is little more than a straight man. Not so. Wetzel has plenty to do in the verbal and the physical comedy departments, too, and he helps make the show feel much shorter than its nearly two-hour running time.

The biggest surprise in “Capital” comes from Dahl’s whip-smart Jenny, a girl prone to temper tantrums who can still hold her own in an argument with her famous father. Like the show itself, she can be silly, but she's never stupid.